The present inventions relates to a new process for synthesizing single carbon bridge bis cyclopentadienyl compounds and metal complexes obtained therefrom. And to the use of these complexes for polymerization and copolymerization of olefins.
The metallocene compounds field has experimented a big development since the first syntheses of these compounds in the fifties (G. Wilkinson et al., J. Am. Chem. Soc., (1953), 75, 1011). This development is basically due to the large increase in the number of applications wherein these compounds are used. So, they can be used as catalysts of hydrogenation, epoxidation, double bond isomerization, ketones reduction, aldolic reaction, synthesis of different substituted olefins, etc., but their largest use is as catalyst components for olefin polymerization, as they can be activated for this use by alumoxanes or other non-coordinative anion precursors (for example boron compounds). In this field metallocenes of group 4 (Ti, Zr, Hf, in particular have been developed, but also metallocenes of groups 3, 5 and 6. Metallocenes have been prepared for working in very different conditions (solution, suspension, mass, gas phase, high pressure and temperature processes, etc.). They have been used for polymerizing and copolymerizing simple I-olefins, basically ethylene and propylene, but also more complex olefins (cyclolefins, diolefins and also olefins with polar groups (see for example W. A. Nugent et al., J. Am. Chem. Soc. (1989), 111, 6435; R. M. Waymouth et al., J. Am. Chem. Soc. (1992), 114, 9679; H. Yasuda et al., Macromol. Chem. Phys, (1995), 196,2417).
For adapting to the different needs of each application, very different metallocenes were synthesized, basically differing by the different substitutions on the cyclopentadienyl rings of the complex, as it is possible to influence in this way, both sterically and electronically, the reactivity of the active center. A specially relevant development was the introduction of at least one bridge connecting the two cyclopentadienyl rings (H. H Britzinger et al., J. Organomet. Chem., (1979), 173, 6270), since it determines the reactivity of the metallocene conditioning its steric nature in two ways: (1) influencing the monomer greater or smaller accessibility to the active center as the bridge largerly determines the angle spread between the cyclopentadienyl rings and (2) preventing the free rotation of the rings and, therefore, determining the symmetry of the whole molecule. On the other hand the bridge can also influence the electronic nature of the metallocene. In this way it has been obtained a better stability of certain metallocenes, a greater or smaller discrimination of the monomers that are incorporated into the polymer because of their size and the possibility of obtaining stereoregular I-olefin polymers (isotactic, syndiotactic, hemiiostactic).
It is known hat in order to obtain specific polymer structures, the use of a single-carbon bridge is preferred (e.g. EP A 351 392). A common process for obtaining this type of bridged ligands comprises reacting a ketone with a cyclopentadienyl in the presence of a strong base, then the obtained fulvene is reacted with another cyclopentadienyl compound again in the presence of a base. Generally these procedure requires a purification of the fulvene or optionally the use of a commercially available one.
Particularly for industrial uses, a one-step process is preferred to a two-step process. A one-step process is developed, for example, in EP 751 143, wherein one or two cyclopentadienyl compounds, at least one being a substituted cyclopentadienyl are reacted with a carbonyl compound in the presence of a base and a phase transfer catalyst; the preferred bases are hydroxides of elements belonging to groups 1, 2 or 13 of the periodic table; in the examples sodium hydroxide is used. Another one-step process is described in EP 722 949. It relates to a process for preparing bis-cyclopentadienyl compounds bridged by a single carbon atom. The compound is prepared by reacting a carbonyl compound with a cyclopentadienyl compound in the presence of a base and of an oxygen-containing solvent having an atomic ratio carbon/oxygen not higher than 3.
These one-step processes make use of strong bases such as sodium or potassium hydroxide; therefore they are not adequate for synthesizing bridged bis cyclopentadienyl compounds wherein the bridge is functionalized with hydrolizable groups. On the other hand, bridged bis cyclopentadienyl compounds having these groups, such as for example trialkyl sililoxy group, bonded to the bridge can be useful to obtain complexes that can be, for example, easily supported on a heterogeneous carrier (see for example EP 839 836). Therefore it could be desirable a new process that permits an easy and one-step synthesis of this kind of compounds.
An object of the present invention is a new process for synthesizing single-carbon bridged bis cyclopentadienyl compounds wherein the bridge contains a hydrolizable group.
A further object of the present invention is a new class of single-carbon bridged bis cyclopentadienyl compounds substituted on the bridge with a hydrolizable group, and the metallocene obtained by the use of these ligands.
Another further object of the present invention is a new class of single carbon bridged metallocenes obtained by hydrolisis of the functional group on the bridge.
Another still further object of the present invention is the use of the previosly described metallocenes for polymerization and copolymerization of olefins.
The present invention relates to bis cyclopentadienyl compounds, wherein the two cyclopentadienyl rings are connected to each other by a single carbon atom characterized by the following general formula I 
wherein
each L, equal to or different from each other, is selected from the group consisting of: 
xe2x80x83wherein
each R1 equal to or different from each other is selected from the group consisting of hydrogen, a monovalent aliphatic or aromatic hydrocarbon group, optionally containing heteroatoms of group 14 to 16 of the periodic table of the elements and boron; optionally two R1 form an aromatic or aliphatic ring; preferably R1 is selected from the group consisting of: hydrogen, C1-C20 alkyl; C3-C20 cycloalkyl; C6-C20 aryl; C2-C20 alkenyl; C7-C20 arylalkyl; C7-C20 alkylaryl; C3-C20 arylalkenyl; CH8-C20 alkenylaryl, linear or branched, optionally substituted by BR2, OR, SiR3, NR2;
wherein each R is independently selected from the group consisting of C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C2-C20 akenyl, C7-C20 arylalalkyl, C7-C20 alkaryl, C8-C20 arylalkenyl, C8-C20 alkenylaryl linear or branched; two or more R can also form an aliphatic or aromatic ring; preferably R is selected from the group consisting of: butyl, propyl, ethyl, methyl;
each R2, equal to or different from each other, is selected from the group consisting of: C1-C20 alkylidene, C3-C20 cycloalkylidene, C2-C20 alkenylidene, C6-C20 arylidene, C7-C20 alkylarylidene, C7-C20 arylalkylidene, C8-C20 arylalkenylidene, C8-C20 alkenylarylidene, linear or branched, optionally containing heteroatoms of group 14 to 16 of the periodic table of the elements or boron; one R2 is optionally absent; in this case A is directly bonded to C and is preferably hydrogen; preferably R2 is selected from the group comprising: butylidene, propylidene, ethylidene, methylidene;
each A, equal to or different from each other, is selected from the group consisting of: hydrogen, OR3, NRR4, or SR5 wherein
each R3 is independently selected from the group consisting of: R, SiR3, SO2R, CR2OR; CR2SR, or any other group used as protective group of alcohols in organic synthesis;
each R4 is independently selected from the group consisting of: R, SiR3, SO2R, or any other group used as protective group of amines in organic synthesis;
each R5 is independently selected from the group consisting of: R, SiR3, CR2OR; CR2SR, or any other group used as protective group of thiols in organic synthesis;
wherein R is independently selected from the group consisting of C1-20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C2-C20 alkenyl, C7-C20 arylalkyl, C7-C20 alkylaryl, C8-C20 arylalkenyl, C8-C20 alkenylaryl linear or branched; optionally two R form a aliphatic or
aromatic ring;
with the proviso that at least one A is not hydrogen.
Preferably A is selected from the group consisting of: hydrogen or OSiR3 non limitative examples of compounds of general formula I are:
1-trimethylsiloxy-4,4-bis(cyclopentadienyl)pentane;
1-trimethylsiloxy-4,4-bis(indenyl)pentane;
1-trimethylsiloxy-4,4-bis(fluorenyl)pentane;
1-trimethylsiloxy-4,4-bis(tetrahydroindenyl)pentane;
1-trimethylsiloxy-4,4-bis(octahydrofluorenyl)pentane;
1,5-bis-trimethylsiloxy-4,4-bis(cyclopentadienyl)pentane;
1,5-bis-trimethylsiloxy-4,4-bis(indenyl)pentane;
1,5-bis-trimethylsiloxy-4,4-bis(fluorenyl)pentane;
1,5-bis-trimethylsiloxy-4,4-bis(tetrahydroindenyl)pentane;
1,5-bis-trimethylsiloxy-4,4-bis(octabydrofluorenyl)pentane;
1-trimethylsiloxy-4-cyclopentadienyl-4-indenyl-pentane;
1-trimethylsiloxy-4-cyclopentadienyl-4-fluorenyl-pentane;
1-trimethylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane;
1-trimethylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane;
1-trimethylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1-trimethylsiloxy-3,3-bis(indenyl)pentane;
1-trimethylsiloxy-3,3-bis(fluorenyl)pentane;
1-trimethylsiloxy-3,3-bis(tetrahydroindenyl)pentane;
1-trimethylsiloxy-3,3-bis(octahydrofluorenyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(indenyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(fluorenyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(tetrahydroindenyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(octahydrofluorenylpentane;
1-trimethylsiloxy-3-cyclopentadienyl-3-indenyl-pentane;
1-trimethylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane;
1-trimethylsiloxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane;
1-trimethylsiloxy-3-cyclopentadienyl-3octahydrofluorenyl-pentane;
1-triethylsiloxy-4,4-bis(cyclopentadienyl)pentane;
1-triethylsiloxy-4,4-bis(indenyl)pentane;
1-triethylsiloxy-4,4-bis(fluorenyl)pentane;
1-triethylsiloxy-4,4-bis(tetrahydroindenyl)pentane;
1-triethylsiloxy-4,4-bis(octahydrofluorenyl)pentane;
1,5-bis-triethylsiloxy-4,4-bis(cyclopentadienyl)pentane;
1,5-bis-triethylsiloxy-4,4-bis(indenyl)pentane;
1,5-bis-triethylsifoxy-4,4-bis(fluorenyl)pentane;
1,5-bis-triethylsiloxy-4,4-bis(tetrahydroindenyl)pentane,
1,5-bis-triethylsiloxy-4,4-bis(octahydrofluorenyl)pentane;
1-triethylsiloxy-4-cyclopentadienyl-4-indenyl-pentane;
1-triethylsiloxy-4-cyclopentadienyl-4-fluorenyl-pentane;
1-triethylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane;
1-triethylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane;
1-triethylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1-triethylsiloxy-3,3-bis(indenyl)pentane;
1-triethylsiloxy-3,3-bis(fluorenyl)pentane;
1-triethylsiloxy-3,3-bis(tetrahydroindenyl)pentane,
1-triethylsiloxy-3,3-bis(octahydrofluorenyl)pentane;
1,5-bis-triethylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1,5-bis-triethylsiloxy-3,3-bis(indenyl)pentane;
1,5-bis-triethylsiloxy-3,3-bis(fluorenyl)pentane;
1,5-bis-triethylsiloxy-3,3-bis(tetrahydroindenyl)pentane;
1,5-bis-trimethylsiloxy-3,3-bis(octahydrofluorenyl)pentane;
1-triethylsiloxy-3-cyclopentadienyl-3-indenyl-pentane;
1-triethylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane;
1-triethylsiloxy-3-cyclopentadienyl-3-tetaydroindenyl-pentane;
1-triethylsiloxy-3-cyclopentadienyl-3-octahydrofluorenyl-pentane;
1-triphenylsiloxy-4,4-bis(cyclopentadienyl)pentane;
1-triphenylsiloxy-4,4-bis(indenyl)pentane;
1-triphenylsiloxy-4,4-bis(fluorenyl)pentane;
1-triphenylsiloxy-4,4-bis(tetrahydroindenyl)pentane;
1-triphenylsiloxy-4,4-bis(octahydrofluorenyl)pentane;
1,5-bis-triphenylsiloxy-4,4-bis(cyclopentadienyl)pentene;
1,5-bis-triphenylsiloxy-4,4-bis(indenyl)pentane;
1,5-bis-triphenylsiloxy-4,4-bis(fluorenyl)pentane;
1,5-bis-triphenylsiloxy-4,4-bis(tetrahydroindenyl)pentane;
1,5-bis-triphenylsiloxy-4,4-bis(octahydrofluorenyl)pentane;
1-triphenylsiloxy-4-cyclopentadienyl-4indenyl-pentane,
1-triphenylsiloxy-4-cyclopentadienyl-4-fluorenyl-pentane;
1-triphenylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane;
1-triphenylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane;
1-triphenylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1-triphenylsiloxy-3,3-bis(indenyl)pentane;
1-triphenylsiloxy-3,3-bis(fluorenyl)pentane;
1-triphenylsiloxy-3,3-bis(tetrahydroindenyl)pentane;
1-triphenylsiloxy-3,3-bis(octahydrofluorenyl)pentane;
1,5-bis-triphenylsiloxy-3,3-bis(cyclopentadienyl)pentane;
1,5-bis-triphenylsiloxy-3,3-bis(indenyl)pentane;
1,5-bis-triphenylsiloxy-3,3-bis(fluorenyl)pentane;
1,5-bis-triphenylsiloxy-3,3-bis(tetrahydroindenyl)pentane;
1,5-bis-tiphenylsiloxy-3,3-bis(octahydrofluorenyl)pentane,
1-triphenylsiloxy-3-cyclopentadienyl-3-indenyl-pentane;
1-triphenylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane;
1-triphenylsiloxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane;
1-triphenylsiloxy-3-cyclopentadienyl-3-octahydrofluorenyl-pentane;
Compounds according to the present invention are synthesized according to a one-step process comprising: contacting a compound (LH) selected from the group consisting of: 
with a compound of general formula II 
in the presence of a metallating compound selected from the group consisting of: organolithium compounds, organosodium compounds, organopotassium compounds, organomagnesium, sodium hydride, potassium hydride, lithium, sodium, or potassium; preferably lithium alkyl, sodium alkyl potassium alkyl; more preferably butyllithium;
increasing the temperature and recovering the product.
Preferably the compound LH is put in contact with the metallating compound and then the compound of formula II is added.
Preferably for one mole of compound of formula II two moles of LH and two moles of the metallating compound are used.
Non limitative examples of compounds of general formula II are;
1-trimethylsiloxy-pentane-2-one,
1-triethylsiloxy-pentane-3-one;
1-triethylsiloxy-pentane-4-one;
1,5-bis-triethylsiloxy-pentane-3-one;
1-trimethylsiloxy-hexane-5-one;
1-trimethylsiloxy-hexane-4-one;
1-trimethylsiloxy-hexane-3-one;
1-trimethylsiloxy-hexane-2-one;
1,6-bis-trimethylsiloxy-hexane-3-one;
1-trimethylsiloxy-heptane-6-one;
1-trimethylsiloxy-heptane-5-one;
1-trimethylsiloxy-heptane-4-one;
1-trimethylsiloxy-heptane-4-one;
1-trimethylsiloxy-heptane-2-one;
1,7-bis-trimethylsiloxy-heptane-4-one;
1-triethylsiloxy-pentane-2-one;
1-triethylsiloxy-pentane-3-one;
1-triethylsiloxy-pentane-4-one;
1,5-bis-triethylsiloxy-pentane-3-one;
1-triethylsiloxy-hexane-5-one;
1-triethylsiloxy-hexane-4-one;
1-triethylsiloxy-hexane-3-one;
1-triethylsiloxy-hexane-2-one;
1,6-bis-triethylsiloxy-hexane-3-one;
1-triethylsiloxy-heptane-6-one;
1-triethylsiloxy-heptane-5-one;
1-triethylsiloxy-heptane-4-one;
1-triethylsiloxy-heptane-3-one;
1-triethylsiloxy-heptane-2-one;
1,7-bis-triethylsiloxy-heptane-4-one;
1-triphenylsiloxy-pentane-2-one;
1-triphenylsiloxy-pentane-3-one;
1-triphenylsiloxy-pentane-4-one;
1,5-bis-1-triphenylsiloxy-pentane-3-one:
1-triphenylsiloxy-hexane-5-one;
1-triphenylsiloxy-hexane-4-one;
1-triphenylsiloxy-hexane-3-one;
1-triphenylsiloxy-hexane-2-one;
1,6-bis-1-triphenylsiloxy-hexane-3-one;
1-triphenylsiloxy-heptane-6-one;
1-triphenylsiloxy-heptane-5-one;
1-triphenylsiloxy-heptane-4-one;
1-triphenylsiloxy-heptane-3-one;
1-triphenylsiloxy-heptane-2-one;
1,7-bis-1-triphenylsiloxy-heptane-4-one;
The process is realized in a temperature range between xe2x88x92100 and 150xc2x0 C., preferably between xe2x88x9278 and 90xc2x0 C., or at the reflux temperature of the used solvents system, it is also possible to vary the temperature during the process. Any kind of solvent compatible with the reactants is used, preferably an aliphatic hydrocarbon, an aromatic hydrocarbon, or an ether, for instance: hexane, toluene, tetahydrofurane (THF) or ethyl ether. The process is preferably carried out under inert atmosphere of, for example nitrogen or argon, and with anhydrous solvents. The skilled man can select the appropriate reaction conditions on the basis of his knowledge and the reactants used.
In a particular embodiment wherein two L groups are different, the single carbon bridged bis cyclopentadienyl compound, object of the present invention, is obtained by a one-pot process comprising: contacting a compound (LH) selected from the group consisting of: 
with a metallating compound selected from the group consisting of: organolithium compounds, organosodium compounds, organopotassium compounds, organomagnesium, sodium hydride, potassium hydride, lithium, sodium, or potassium; preferably lithium alkyl, sodium alkyl, potassium alkyl; more preferably butyllithium;
with a compound of general formula II 
adding a second compound LH different from the first one;
adding a second amount of metallating compound as above defined;
increasing the temperature and recovering the product.
Preferably the compound LH is contacted with the compound of formula II in the presence of a metallating compound, then a second compound LH and the metallating compound are mixed; the mixture is then introduced to the reaction mixture.
Preferably for one mole of compound of formula II one mole of the first LH compound, one mole of the second one and two moles of a metallating compounds are used. More preferably an quimolar mixture of LH and metallating agent is put in contact with a compound of formula II, then an equimolar mixture of an LH compound different from the first one and a metallating agent is added to the reaction product.
The skilled man can select on the basis of his knowledge the appropriate temperatures of the first and the second phase that depends from the cyclopentadienyl compounds used. Usually the first phase is performed at a temperature range from xe2x88x9278xc2x0 C. to room temperature and the second phase at a temperature range from xe2x88x9278xc2x0 C. to the boiling point of the solvent.
The single-carbon bridged cyclopentadienyl compounds object of the present invention are used for synthesizing metallocene complexes of general formula III 
Wherein:
Each Lxe2x80x2 is independently a cyclopentadienyl compound and forms with the metal a xcex75 complex, it is selected from the group consisting of: 
M is a tranition metal of groups 3-6 of the periodic table; preferably it is selected from the group consisting of zirconium, titanium or hafnium;
m is a number coinciding with the oxidation state of the transition metal;
Each X, equal to or different from each other, is selected from the group comprising, halogen, hydrogen, OR, N(R)2, C1-C20 alkyl or C6-C20 aryl; preferably it is halogen.
Examples of metallocenes of formula III are:
(1-trimethylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-4,4-bis(fluoreny)pentane)zirconium dichloride;
(1-trimethylsiloxy-4,4-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-4,4-bis(fluorenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-4,4-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconiurn dichloride;
(1-trimethylsiloxy-4-cyclopentadienyl-4-indenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-4-cyclopentadienyl-4-fluorenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-3,3-bis(indenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-3,3-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichloride;
(1,5-bis-trimethylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride,
(1,5-bis-trimethylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1-trimethylsiloxy-3-cyclopentadienyl-3-indenyl-pentana)zirconium dichloride;
(1-trimethylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane)zirconium dichloride;
(1-trimethylsiloxy-3-cyclopentadienyl-3-octahydrofluorenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-triethylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-4,4-bis(fluorenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-4,4-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-4,4-bis(fluorenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-4,4-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-4-cyclopentadienyl-4-indenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-4-cyclopentadienyl-4fluorenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-triethylsiloxy-3,3-bis(indenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride,
(1,5-bis-triethylsiloxy-3,3-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichoride;
(1,5-bis-triethylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1,5-bis-triethylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1-triethylsiloxy-3-cyclopentadienyl-3-indenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane)zirconium dichloride;
(1-triethylsiloxy-3-cyclopentadienyl-3-octahydrofluorenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-4,4-bis(fluorenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-4,4-bis(tetahydroindenyl)pentane)zirconium dichoride;
(1-triphenylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-4,4-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-4,4-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-4,4-bis(fluorenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-4,4-bis(tetraydroindenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-4,4-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-4-cyclopentadienyl-4-indenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-4-cyclopentadienyl-4-fluorenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-3,3-bis(indenyl)pentane)ziconium dichloride;
(1-triphenylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-3,3-bis(cyclopentadienyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-3,3-bis(indenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-3,3-bis(fluorenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-3,3-bis(tetrahydroindenyl)pentane)zirconium dichloride;
(1,5-bis-triphenylsiloxy-3,3-bis(octahydrofluorenyl)pentane)zirconium dichloride;
(1-triphenylsiloxy-3-cyclopendienyl-3-indenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-3-cyclopentadienyl-3-fluorenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane)zirconium dichloride;
(1-triphenylsiloxy-3-cyclopentadienyl-3-octahydrofluorenyl-pentane)zirconium dichloride;
The metallocene complexes of general formula III are synthesized according to a process comprising the following steps:
a) reacting a compound of general formula I with two equivalents of a strong base selected from the group consisting of: organolithium compounds, organosodium compounds, organopotassium compounds, organomagnesium, sodium hydride, potassium hydride, lithium, sodium, or potassium; preferably lithium alkyl, sodium alkyl, potassium alkyl; more preferably butyllithium;
b) reacting the bimetallated reaction product with one equivalent of a compound of general formula MXmEq wherein E is an ether or an amine forming an adduct with M and q is 0, 1, 2, 3 or 4.
With compounds of formula M it is possible to synthesize compounds of general formula IV: 
wherein each B, equal to or different from each other, is selected from the group consisting of: OH, NRH or SH by hydrolizing the corresponding oxygen, nitrogen or sulfur containing groups.
Examples of such compounds are
(1-hydroxy-4,4-bis(cyclopentadienyl)pentane) zirconium dichloride;
(1-hydroxy-4,4-bis(indenyl)pentane) zirconium dichloride;
(1-hydroxy-4,4-bis(fluorenyl)pentane) zirconium dichloride;
(1-hydroxy-4,4-bis(tetrahydroindenyl)pentane) zirconium dichloride;
(1-hydroxy-4,4-bis(octahydrofluorenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-4,4-bis(cyclopentadienyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-4,4-bis(indenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-4,4-bis(fluorenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-4,4-bis(tetrahydroindenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-4,4-bis(octahydrofluorenyl)pentane) zirconium dichloride;
(1-hydroxy-4-cyclopentadienyl-4-indenyl-pentane) zirconium dichloride,
(1-hydroxy-4-cyclopentadienyl-4-fluorenyl-pentane) zirconium dichloride;
(1-hydroxy-4-cyclopentadienyl-4-tetrahydroindenyl-pentane) zirconium dichloride;
(1-hydroxy-4-cyclopentadienyl-4-octahydrofluorenyl-pentane) zirconium dichloride;
(1-hydroxy-3,3-bis(cyclopentadienyl)pentane) zirconium dichloride;
(1-hydroxy-3,3-bis(indenyl)pentane) zirconium dichloride;
(1-hydroxy-3,3-bis(fluorenyl)pentane) zirconium dichloride;
(1-hydroxy-3,3-bis(tetrahydroindenyl)pentane) zirconium dichloride;
(1-hydroxy-3,3-bis(octahydrofluorenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-3,3-bis(cyclopentadienyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-3,3-bis(indenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-3,3-bis(fluorenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-3,3-bis(tetrahydroindenyl)pentane) zirconium dichloride;
(1,5-bis-hydroxy-3,3-bis(octahydrofluorenyl)pentane) zirconium dichloride;
(1-hydroxy-3-cyclopentadienyl-3-indenyl-pentane) zirconium dichloride;
(1-hydroxy-3-cyclopentadienyl-3-fluorenyl-pentane) zirconium dichloride;
(1-hydroxy-3-cyclopentadienyl-3-tetrahydroindenyl-pentane) zirconium dichloride;
(1-hydroxy-3-cyclopentadienyl-3-octahydrofluorenyl-pentane) zirconium dichloride;
The skilled man can select reactants and conditions for performing this hydrolization reaction; for example compounds wherein the group A is OSiR3 are hydrolized to form an OH group by using silica gel, or any other chemical reaction with the appropriate reactants that deprotects the funtional group.
The metallocenes of the present invention are particularly adequate as catalyst component for polymerizing olefins, preferably alpha-olefins in combination with a cocatalyst. Illustrative but non-limiting non-limiting examples of co-catalysts are: aluminoxanes (MAO, MMAO, etc.), combinations of alkyl aluminiums (such as trimethylaluminum, triethylaluminium, tributylaluminium, etc.) and boron Lewis acids (such as trifluoroborate, trispentafluorophenylborane, tris[3,5-bis(trifluoromethyl)phenyl]borane, etc.), Lewis acids (dimethylanilium tetrakis(pentafluorophenyl)boron, HBF4, AgBF4, AgPF6, AgSbF6, silver tetrakis[3,5-bis(trifluoromethyl)phenyl]borate sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, etc.).
The catalyst component of the present invention, i.e. the metallocene complex of formula III or IV (preferably when at least a hydrolizable group A in formula III is OSiR3 or when in formula IV at least one B is OH), is especially fit for being supported on a proper inorganic support as described in EP 839 836. As supporting material, any type of inorganic oxides are used, for example inorganic oxides such as: silica, alumina, silica alumina, aluminum phosphates and mixtures thereof, obtaining supported catalysts with contents in transition metals between 0.01 and 4% by weight, preferably between 0.1 and 1%. A particularly preferred support is silica calcined at a temperature between 600xc2x0 C. and 800xc2x0 C. and also MAO modified silica.
A process that is fit for preparing supported catalysts according to this invention comprises the following steps:
a) reacting, under anhydrous conditions and inert atmosphere, a solution of at least one metallocene complex of formula III or IV, with a suspension of the supporting material at a temperature between xe2x88x9220xc2x0 C. and 90xc2x0 C. The solvent used for this procedure is an aliphatic or aromatic hydrocarbon.
b) filtration and washing with a aliphatic or aromatic hydrocarbon.
Another process that can properly be used comprises the following steps:
a) reacting at least one metallocene complex of formula III or IV with the supporting material by using a solution of the compound to heterogenize;
b) eliminating the solvent through evaporation;
c) warming the solid residue up to a temperature between 25 and 150xc2x0 C.
Besides, the resulting residue obtained by this process, is optionally subjected to washing and subsequent filtration.
The amount of metallocene of formula III or formula IV which is anchored in these conditions directly depends on the concentration of the reactive groups present in the support. For this reason silica, for example, should preferably have been calcinated at a temperature between 600xc2x0 C. and 800xc2x0 C.
A solid catalyst system is obtained by adding to the solid catalyst component a cocatalyst, for example alumoxane, boron compounds or mixtures thereof, at any step of the processes described above. In a particularly advantageous process the cocatalyst, preferably alumoxane, is added to the support, preferably silica, and then the treated support is reacted with the metallocene of formula III or IV according to the process described in patent 98500101.5.
For the polymerization in solution, the cocatalyst is partly premixed with a solution of a metallocene complex according to formula III or IV and is partly added directly to the reaction medium; alternatively, the catalyst is directly added to the polymerization medium, which contains the cocazalyst.
For the polymerization in suspension, the cocatalyst either is previously mixed with the supported solid catalyst or it is added to the polymerization medium before the supported catalyst, or both operations are sequentially realized.
The most proper polymerization procedure changes according to the chosen type of polymerization process (solution, suspension, slurry or gas phase).
The process consists in putting in contact the monomer, or, in certain cases, the monomer and the comonomer, with a catalytic composition according to the present invention that includes at least one metallocene of formulas III or IV, at a proper temperature and pressure.
C2-C8 alpha-olefins, such as ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene are used as monomer. In case ethylene is used as the monomer, it is polymerized either one or in combination with a comonomer. Preferred comonomers are propylene, butene, hexene, octene or branched ones such as 4-methyl-1-pentene and are used in proportions from 0.1 to 70% by weight of the total of the monomers. In the case of homopolymerization of ethylene the density of the obtained polymers ranges between 0.950 and 0.965 kg/cm3; in the case of copolymerization of ethylene, the density is as low as 0.900 kg/cm3.
In the particular case of the polymerization technique known as suspension process or controlled particle morphology process, the used temperature will be between 30xc2x0 and 110xc2x0 C., the same which is typically used in gas phase, while for the solution process the usual temperature will be between 120xc2x0 and 250xc2x0 C.
The used pressure changes according to the polymerization technique; it ranges from atmospheric pressure to 350 MPa.